The present invention relates to a new and improved method and apparatus for transmitting data in a manufacturing machine, especially a yarn or thread manufacturing machine.
In its more particular aspects, the present invention specifically relates to a new and improved method and apparatus for transmitting data in a manufacturing machine, especially a yarn or thread manufacturing machine containing a plurality of production stations, a plurality of associated monitoring locations, a plurality of respective monitoring sensors, and a central control unit communicating with the plurality of monitoring locations.
In a known method or circuit arrangement for transmitting data in a textile machine of the aforementioned type such as known, for example, from European Patent Publication No. 0,090,766, published Oct. 5, 1983, and the cognate U.S. Pat. No. 4,512,028, granted Apr. 16, 1985, an electronic scanner is utilized for monitoring a multitude of production stations or thread running locations in the textile machine. For this purpose, each production station or thread running location is provided with a monitoring location in the form of a measuring head for detecting thread rupture or breakage. The output signals of the measuring heads are supplied, via a signal line and by means of an interrogation or scanning operation, to a central unit which constitutes an indicating or control device. This known circuit arrangement is distinguished by the fact that each measuring head is associated with a bistable controller having a data input and a clock input. The bistable controllers are series connected by means of their data inputs and the clock inputs are connected to a common clock pulse generator.
Due to the series connection of the bistable controllers there exists the disadvantage that a failure in one of the bistable controllers will result in failure of the entire circuit arrangement. This is a very significant disadvantage considering that the textile machine frequently contains more than 1000 production stations or thread running locations and the risk of failure is always existent at one of such a great number of production stations or thread running locations. Also, the known circuit arrangement results in a wiring layout and expense which may be relatively small in comparison to other known circuit arrangements but still is undesirably high.
A specific prior art thread break detector is described in Swiss Patent No. 479,478, granted Oct. 15, 1969. In an improved thread breakage or rupture sensor such as known, for example, from German Patent No. 2,313,959, granted Mar. 31, 1977, the output signal of the thread breakage or rupture sensor is evaluated in an evaluation circuit. The output signal of the evaluation circuit triggers an alarm or control device for automatically stopping or shutting down the thread delivery or supply. Such an evaluation circuit is provided for each thread breakage or rupture sensor, however, it is not explained in the aforementioned German patent in which manner the individual alarm signals present at the output terminals of such evaluation circuits are transmitted to a central control unit.
In a known apparatus for monitoring an operating sequence of production stations of a textile machine with respect to thread breakage or rupture such as known, for example, from German Patent No. 2,731,019, granted Nov. 9, 1978, there is disclosed the possibility of passing a sensor head for receiving electrical signals in a contactless manner, past the production stations on a guide rail. A traction band for the sensor head is constructed as a metallic, electrically conductive traction band which provides electrical connection between the sensor head and a central control unit.
It is generally desired and significantly important for all manufacturing machines containing a plurality of production stations of the same type that a predetermined state or condition or event can be detected at individual ones of the plurality of production stations, the production or manufacturing operation at such individual production stations can be adapted to such predetermined state or condition or event, and data related to such predetermined state or condition or event at all of the plurality of production stations ultimately can be transmitted to a central evaluation or control unit. In, for example, a ring spinning machine containing a plurality of spinning stations, a thread breakage or rupture sensor is present at each one of the plurality of spinning stations and detects whether the respective spinning station produces yarn or thread in a normal spinning operation.
An electronic amplifier transforms the signal produced by the thread breakage or rupture sensor into a suitable electrical triggering signal for a slubbing stopping device which is associated with the respective spinning location. The slubbing stopping device, in turn, effects an interruption in the slubbing supply as soon as the normal operation of the spinning station is disturbed. The information "spinning station disturbed" is communicated to the central evaluation or control unit via a signal line. The central evaluation or control unit, in turn, informs the operator about the number and location of the thus detected disturbed spinning stations and generates statistical data with respect to the course of the entire manufacturing operation.
It should be emphasized at this point that in all hitherto known solutions found for these problems in textile machines, there was required a considerable electrical wiring layout and expense in order to ensure the electrical power supply for the thread breakage or rupture sensor, the electronic evaluation circuits and the triggering operation at each one of the plurality of production stations as well as to transmit data from the various stations to the central evaluation or control unit. The prior art circuit arrangements rely upon separately providing the electrical power supply and the data transmission.
Various other methods or procedures are also known in the art for combining the data related to the individual production stations in groups and transmitting the entire group of data in coded form via a single pair of lines or conductors. Corresponding coding methods are known and standardized to a substantial extent by utilizing, for example, serial interfaces such as the serial interface RS 232. However, such coding operation is associated with considerable electronic effort and expense and is, in any event, prohibitively high for utilization at each individual production station.